Sand sifting Goby

I have this little problem in my tank. I have a 75gal FOWLR with dsb. I bought a little Goby that sifts sand through his mounth as a means for a little sand stiring. Well this fish creates one heck of a sand storm when the lights are on, so much so that my live rock gets covered with sand. In some places the coralline algae (which was a purple pink color ) is turning to a greenish white color. Not sure what I can do to fix this. Any ideas???

Well the rock is throughout the whole tank and I have two 1200 maxi-jet powerheads and a 200 gph return from refugium. Its like a very fine sand storm everywhere